Rcs1-chapter1
61
1 Reinforced concrete structures 1 - Eurocodes RCS1 Professor Marwan SADEK https://www.researchgate.net/profile/Marwan_Sadek https://fr.slideshare.net/marwansadek00 Email : [email protected] If you detect any mistakes, please let me know at : [email protected]
-
Upload
marwansadek00 -
Category
Education
-
view
143 -
download
0
Transcript of Rcs1-chapter1
1
Reinforced concrete
structures 1 - Eurocodes
RCS1
Professor Marwan SADEKhttps://www.researchgate.net/profile/Marwan_Sadek
https://fr.slideshare.net/marwansadek00
Email : [email protected]
If you detect any mistakes, please let me know at : [email protected]
2
PLAN – RCS1
M. SADEK
Ch 1 : Generalities – Reinforced concrete in practice
Ch 2 : Evolution of the standards – Limit states
Ch 3 : Mechanical Characteristics of materials – Constitutive relations
Ch 4 : Durability and Cover
Ch 5 : Beam under simple bending – Ultimate limit state ULS
Ch 6 : Beam under simple bending – serviceability limit state SLS
Ch 7 : Section subjected to pure tension
3
Selected ReferencesFrench BAEL Code (91, 99)
Règles BAEL 91 modifiées 99, Règles techniques de conception et de calcul des ouvrages et constructions en béton armé, Eyrolles, 2000. J. Perchat (2000), Maîtrise du BAEL 91 et des DTU associés, Eyrolles, 2000. J.P. Mougin (2000), BAEL 91 modifié 99 et DTU associés, Eyrolles, 2000.….
EUROCODES H. Thonier (2013), Le projet de béton armé, 7ème édition, SEBTP, 2013. Jean-Armand Calgaro, Paolo Formichi ( 2013) Calcul des actions sur lesbâtiments selon l'Eurocode 1 , Le moniteur, 2013. J. M. Paillé (2009), Calcul des structures en béton, Eyrolles- AFNOR, 2009. Jean Perchat (2013), Traité de béton armé Selon l'Eurocode 2, Le moniteur,2013 (2ème édition) Manual for the design of concrete building structures to Eurocode 2, TheInstitution of Structural Engineers, BCA, 2006. A. J. Bond (2006), How to Design Concrete Structures using Eurocode 2, Theconcrete centre, BCA, 2006.https://usingeurocodes.com/
M. SADEK
4
In addition to Eurocodes, the references that are mainly used to prepare this course material are : Thonier 2013
Perchat 2013
Paillé 2009
Some figures and formulas are taken from
Cours de S. Multon - BETON ARME Eurocode 2 (available on internet)
Cours béton armé de Christian Albouy
M. SADEK
5M. SADEK
CHAPTER 1
Generalities
Reinforced concrete in practice
6
Concrete Constructions , Buildings and Civil Works
Modern Constructions
Reinforced Concrete: Invented by François Hennebique in 1886 . Heused it in 1899 in the construction of the first civilReinforced Concrete bridge "Camille-de-Hogues
M. SADEK
(1848) Joseph Louis Lambot (cultivaor) : Hydraulic lime concrete with steel reinforcement. Achievement of a small boat
7
REINFORCED CONCRETE
PRESTRESS CONCRETE
Invented by EUGÈNE FREYSSINET , 1928
M. SADEK
Concrete Constructions , Buildings and Civil Works
Modern Constructions
8
The Reinforced concrete is
composed of :
Concrete (High compressive strength)
Steel Reinforcement (High compressive and tensile strength)
M. SADEK
Concrete Constructions , Buildings and Civil Works
Modern Constructions
9
Buildings : residential, offices, hospitals, schools..
Civil Works : Bridges, Dams, Retaining structures, ports,
airports, non ballasted tracks
M. SADEK
Concrete Constructions , Buildings and Civil Works
Modern Constructions
10M. SADEK
Concrete Constructions , Buildings and Civil Works
Modern Constructions
11M. SADEK
Concrete Constructions , Buildings and Civil Works
Modern Constructions
12
Breeze blocks – Concrete blocks
Cement Slurry / Grout: Cement + water
Cement mortar : Cement + water + Sand
Concrete
M. SADEK
13
Concrete Material (Cement concrete)
M. SADEK
Formulation (Several Methods: Baron, Bolomey, Dreux .. )
Cement (hydraulic binder: Setting by hydration)
Water (hydration of the binder)
Aggregates (Sand + gravel)
14
Road pavements
Surface layer
M. SADEK
Another concrete
Asphalt Concrete(Hydrocarbon Binder )
15
CEMENT
M. SADEK
a binder, a substance that sets and hardens
The word "cement" traces to the Romanscrushed rock with burnt lime as binder
(construction of ports)
Modern Cement : Portland Cement
(Louis Joseph Vicat 1817 et Joseph Apsdin 1824)
16
CEMENT
The cement is an essential component of the Concrete
Acting as a glue, binding everything together into a hard block
The cement is a hydraulic binder thats sets by hydration (contact with the water)
M. SADEK
ClinkerLimestone Clay
Cement
17
CONCRETE
M. SADEK
18M. SADEK
800 liters Gravels+
400 liters sand +
300 to 400 kg of cement+
175 Liters of waters
W/C : around 0.4 (weight ratio)
* Adjuvants : set accelerators, set retarders..
19M. SADEK
Lean concrete (blinding concrete)
Cement content : 100 à 150 kg / m3
20M. SADEK
COMPOSITION and Pouring of Concrete
Formulation
Concrete mixing system (Concrete mix truck)
Concrete formwork, Shuttering (in temporary mould of variable sizes, into which fresh concrete is poured)
Placing Reinforcement Steel
Pouring
Vibration (reduce honeycombing and segregation)
21
Pouring of Concrete
Vidéo 1 : Ground Slab
M. SADEK
22
Concrete : Brittle material
- Good Compressive Strength
- Low Tension Strength
M. SADEK
23
The Concrete properties depend on the Formulation
Compressive Strength
Low Creep and Shrinkage
Workability (easily placed and compacted homogeneously)Waterproofness, freeze-thaw resistance, abrasion ..)
( !Reasonable PRICE!)
Important PARAMETERS : W/C ratio, aggregates grading ,temperature ..
* Admixtures / additives: set accelerators, set retarders...
M. SADEK
24
Grading Curve - Aggregates
M. SADEK
25
Admixtures / additives
M. SADEK
Plasticizers and superplasticizers that improve the
workability
Set Acceleretors in cold climate conditions
Admixture to entrain micro air bubbles in concrete
exposed to freeze/thaw cycles
Waterproof concrete Admixture
26
Concrete Moulding & Placing Reinforcement Steel
M. SADEK
27M. SADEK
Concrete Moulding & Placing Reinforcement Steel
28M. SADEK
Principle of Reinforced Concrete
29
Compressive Stress in Concrete : The hardened concrete should
attain an adequate compressive stress
(The tensile strength of the concrete is low !)
Tensile Stress in Steel (main function)
(Sometimes, the Steel is added in compression face, to help the concrete resist compression )
M. SADEK
Principle of Reinforced Concrete
30
Tension :
Supported by steel
Concrete under compression
M. SADEK
Principle of Reinforced Concrete
31
Vidéo 2 : Loading test of a RC beam
M. SADEK
Principle of Reinforced Concrete
32M. SADEK
Principle of Reinforced Concrete
The behaviour of Reinforced concrete is based on bond
between Steel & Concrete : The total bond between the steel
and concrete is sufficient to keep them acting together (same
strain)
The coefficient of thermal expansion of concrete is very
close to that of steel (if not => RC structure don’t exist)
33M. SADEK
In prestress concrete, the steel cables provide compressive stresses
that overcome concrete's natural weakness in tension
34
Compressive strength
CHARACTERISATION OF CONCRETE
M. SADEK
The compressive strength ofconcrete is the most commonperformance measure used by theengineer in designing buildings andother structures.The compressive strength ismeasured by breaking cylindricalconcrete specimens in acompression-testing machine
Specimen size : 16 cm x 32 cm (6x12 inches US)
35
36
Acoustic
Thermal
Fire resistance
…
SPECIFICITIES
Density ??
37
STEEL OF R.C.
Main Function : resist to tensile strength
Twisted bar or High bond : in general (folding out is prohibited)
Round or plain bars : Cadres and stirrups – Transverse reinforcement (folding out is allowed)
Bond between Steel / Concrete
(The cover of concrete in the tensioned part, protect the steel against corrosion)
Longitudinal / transverse renforcement
M. SADEK
38M. SADEK
STEEL OF R.C
39M. SADEK
STEEL OF R.C
Longitudinal Reinforcement(Normal stress - Bending)
Transverse Reinforcement(Shear Stress)
40
Steel : bent, cut, weld ..
A minimum diameter of the mandrel is required
No failure of the concrete inside the bend
Avoiding cracks in the bar to preserve the bond characteristics
M. SADEK
41
Video n°3 : steel bender
M. SADEK
42
It can be cast to take the shape required, making it widely used in
precast structural components.
Long service life with low maintenance cost
High fire resistance
In some types of structures, such as dams, piers, and footings, it
is the most economical structural material
Advantages of RC
43
It has a low tensile strength of about one-tenth of its
compressive strength;
High self-weight in case of long span where steel structures
become more competitive
Low thermal insulation
High Cost in case of demolition or transformation of
concrete structures
Disadvantages of RC
44
Feasibility stud, geotechnical tests
Schematic design , Architectural plans
BE Structure
Analysis of internal forces – Load assessment
RC Design
Construction drawings
DESIGN STEPS
45
RC Elements of a building
M. SADEK
Foundations, Gbeams
Columns, beams
Slab
chaining , lintel
…
46
Main / secondary beams - solid slab
M. SADEK
47
Beams / Columns
48
Frames (Beams / Columns)
M. SADEK
49M. SADEK
Sections - Columns
50
Video n°4 : RC Walls
RC Walls
51
Footing planIsolated Footing / Tie beams
M. SADEK
52M. SADEK
Isolated Footing
53
Strip Foundation
M. SADEK
54
Different Configurations
M. SADEK
55
Deep foundations - piles
M. SADEK
56
Precast element
M. SADEK
57
Ribbed slab (hourdis)
Video n°5
M. SADEK
58
Load Transfer
59
3D modeling
60M. SADEK
3D modeling
61
Example – load on column
M. SADEK
